The R&R valve/oil separator unit failed on my 2015 Audi S4 at approximately 71,000 miles. This unit, when fails, can mix the oil and anti-freeze which can seize the engine. I was able to catch the problem before engine failure. Minneapolis Audi repaired the vehicle this week, 1/10/23. There were NO warning indicators except noise. Various media sources have stated that this is a known engine failure concern between 60-90K miles for this engine. Audi does not recognize this as a safety or warranty concern.
The worst 2015 Audi S4 problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
- Engine1
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
- Engine1
Recalls 1
Air bags
- What is wrong
- Volkswagen Group of America, Inc. (Volkswagen) is recalling certain model year 2013-2015 Audi A4 and S4 vehicles manufactured February 16, 2012, to October 21, 2014, and 2013-2015 Audi Allroad vehicles manufactured March 12, 2012, to October 21, 2014. Due to an improper algorithm in the air bag control module, if a crash necessitates deployment of the side air bags, a second impact to the front of the vehicle may not command the front air bags to also deploy.
- Risk
- If the front air bags do not deploy in the event of a secondary impact to the front of the vehicle, there is an increased risk of occupant injury.
- Remedy
- Volkswagen will notify owners, and Audi dealers will update the air bag control unit software, free of charge. The recall began on November 14, 2014. Owners may contact Audi customer service at 1‑800‑822‑2834. Volkswagen's number for this recall is 69K5.
Recall number 14V667000 · Recall details
Technical service bulletins for the 2015 Audi S4 696
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- This bulletin provides informaiton on the use of the PICO-NVH tool (VAS 611 015).
- This bulletin proides service information when there is a prompt to take over the steering wheel (hands...
- This bulletin provides information when the starter battery is discharged or malfunctioning.
- This bulletin provides information to aid in diagnosing the vehicle locking system.
- This bulletin provides information when the engine is not runing smoothly; all gas engines.
- This bulletin provides information on VIN plates, Safety Certification labels, and ordering procedures.
- This bulletin provides information for reporting safety related information to the manufacturer.
- This bulletin states that technicians are required to report to the manufacturer when a vehicle has...
- This bulletin provides service information regarding exterior glass cleaning.
- This bulletin provides information about vibrations and rotational steering vibrations.
2015 Audi S4 fuel economy
Official EPA estimates in miles per gallon (MPGe for electric). Ranges cover trims that share the same engine.
| Engine | Drive | City | Highway | Combined |
|---|---|---|---|---|
| 3.0L 6‑cyl | AWD | 17-18 | 26-28 | 20-21 |
What 2015 Audi S4 owners say
Most recent owner complaints, unedited.
Compare the 2015 Audi S4
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Questions about the 2015 Audi S4
Is the 2015 Audi S4 reliable?
Owners have filed 1 complaint about the 2015 Audi S4, fewer than a typical S4 model year.
What is the 2015 Audi S4 year score?
The 2015 Audi S4 scores 95 out of 100 (good). The score compares it with the other model years of the Audi S4: 75 is a typical year, 50 means twice the usual complaints, and serious complaints and recalls lower it.
What is the most common problem with the 2015 Audi S4?
Engine and cooling, with 1 complaint.
How many recalls does the 2015 Audi S4 have?
1 recall, covering air bags.
What year does the Audi S4 have bad engine?
The Audi S4 model years with the most engine complaints are 2004 (15 complaints), 2010 (15 complaints) and 2001 (11 complaints).
What gas mileage does the 2015 Audi S4 get?
Official estimates for the 2015 Audi S4 range from 20 to 21 mpg combined. The most efficient version (3.0L 6-cyl, AWD) gets 17-18 city and 26-28 highway.
VIN decoder
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